Perinatal Factors and Neuroimaging Changes for Brain Maturation Among Adolescents.

Safety evaluation can be defined as the comprehensive process of assessing one’s safety through the detection, prediction, and integration of safety information to guide behavior (). The ability to accurately evaluate safety is important for supporting adaptive behaviors, such as exploration and learning. Accurately evaluating safety may be especially challenging during adolescence for multiple reasons (, ). First, the adolescent period requires navigating novel environments to gain independence and experience, which may result in increased uncertainty with respect to safety (, , , , ). Second, adolescents undergo crucial neurobiological changes (e.g., prefrontal-limbic development), which can impair safety evaluation due to its reliance on bottom-up as well as top-down neural processes (, , ). These features of adolescent development may help explain the onset of mental health disorders and risky behaviors during this period. Adolescence is a peak period for the emergence of anxiety disorders and related mental health difficulties, which often involve biased judgments about safety (, , ). Adolescence is also marked by altered risk-taking behaviors, including increased reckless driving and substance abuse, which similarly involve challenges in evaluating safety and the potential consequences of unsafe choices (, ). To date, most of what is known about safety evaluation stems from fear conditioning research (, ), although definitions of safety subtly differ across paradigms (see ). Fear conditioning paradigms are used to understand both threat and safety learning. In differential fear conditioning, individuals learn that the absence of an aversive outcome signals safety. In this paradigm, a neutral conditioned stimulus (CS+) is paired with an aversive unconditioned stimulus (US, e.g., shock), while another conditioned stimulus (CS-) is not paired with the US. Over time, the CS + elicits conditioned responses (CR, e.g., freezing), whereas the CS- serves as a safety signal. During extinction, the CS + is no longer paired with the US, such that the previously threatening stimulus is neutralized and comes to signal safety. In conditioned inhibition, while stimulus A alone indicates threat, when combined with a second, neutral stimulus X (AX-), the expected threat is neutralized and the AX- pair serves to signal safety. In conditional discrimination, AX is paired with the US (AX+) and BX is paired with the absence of the US (BX-), such that presenting A with B reduces fear responses relative to AX + , reflecting transfer of safety from B to A. Comparison of traditional fear conditioning paradigms with the current study. Expected perceived safety reflects the safety perception participants would have if they accurately learned the task contingencies. In fear conditioning, safety is increased by modifying the threat through an unrelated neutral cue (differential conditioning, CS-), threat neutralization (extinction), or the addition of a modifier that signals threat neutralization (conditioned inhibition and conditional discrimination). In the current study, safety is increased by modifying resources at the agent’s disposal (through protection) without modifying the threat.